X-ray apparatus



April 18, 0 o. c. HOLLSTEIN 2,504,687'

X-RAY APPARATUS Filed April 16, 1947 3 Sheets-Sheet l INVHENTOR 0. 6.#0145727. 5

ATTORNEY 0. C. HOLLSTEIN X-RAY APPARATUS April 18, 1950 3 Sheets-Sheet 2Filed April 16, 1947 IINVENTOR 0. c. HULL 5/27/14 W mum ATTORN EY April18, 1950 o. c. HOLLSTIEIN X-RAY APPARATUS 3 Sheets-Sheet 5 Filed April16, 1947 iNV EN FOR a. 0. #0445229. BY (F Q (WM ZM ATTORNEY PatentedApr. 18, 1950 X-RAY APPARATUS Oswald Conrad Hollstein, Secaucus, N. J.,as-

signor to Westinghouse Electric Corporation, East Pittsburgh, Pa., acorporation of Pennsyl- Vania Application April 16, 1947, Serial No.741,796

9 Claims. (Cl. 25058) The present invention relates to X-ray apparatusand more particularly to X-ray examination tables of the tilting typeused by the roentgenologist for the making of radiographic andfluoroscopic examinations.

Tables of this type for enabling a patient, when reclining upon thetable, to be moved to various angular positions from below thehorizontal, or what is known as the Trendelenberg position, to avertical position are known to the art. The most familiar type has beenthat with which two X-ray tubes are employed, with one of these tubesbeing disposed below the table top and used primarily for fiuoroscopy,and the other X-ray tube being carried by a tube column movable upon arail longitudinally of the table, and suspended above the table top forthe primary purpose of radiography.

In order to decrease the floor area formerly required as well as toeliminate the necessity for two X-ray tubes, the more modern design ofX-ray examination tables provides for a single X-ray tube which isrotatable about an axis from its support, to positions above or belowthe table top as conditions require. This latter type apparatus presentsmany problems and has,;heretofore, possessed several disadvantages. Forexample, when used for fluoroscopy it is necessary that the X-ray tubewhich, during such examination is disposed below the table top, followmovement of the fluorescent screen with the latter in turn being movabletoward and away from the table top. Moreover, it is essential forefiicient operation that the X-ray tube and screen be movable in unisonsubstantially the full length of the table to enable the examination ofa patient from one extremity to the other. Inasmuch as the various partsare of substantial weight, one of the greatest problems in this type ofexamination table has been that of counter-balancing the parts tofacilitate ease of movement and protection of the patient, with mosttypes counterbalancing the movable parts only when the table is moved tothe vertical position.

During the making of a radiographic examination, when the X-ray tube isdisposed above the table top, the fluorescent screen constitutes anobstruction which must be moved out of the field and retained safely insuch position to prevent accidental contact with the X-ray tube or thepatient. A further disadvantage heretofore existent in single tube X-rayexamination tables has been the fact that movement of the X-ray tuberelative to the table top, both longitudinally and perpendicularthereto, has been considerably restricted especially insofar as enablingthe X-ray tube to be moved to as short a space as approximately sixinches from the table top. I

It is accordingly the primary object of the present invention to providean X-ray examina tion table of the tilting type wherein a single X-raytube is employed which is movable to posltions both above and below thetable top with certain movable parts being counter-balanced in allpositions of the table to facilitate ease of movement thereof.

Another object of the present invention is the provision of an X-rayexamination table in which the fluorescent screen and X-ray tube supportare fully counter-balanced by the same counterweight thus decreasing thesize of the equipment which would be otherwise required.

Another object of the present invention is the provision of an X-rayexamination table wherein the X-ray tube can be moved to substantiallyany position above the table top and the fluorescent screen is socounter-balanced as to be automatically moved out of the X-ray fieldduring the making of a radiographic examination.

A further object of the present invention is the provision of an X-rayexamination table wherein all the moving parts are counter-bal anced bya single counter-weight which decreases the size and weight of theentire apparatus with such counter-weight selectively operating as eachpart is moved.

Still further objects of the present invention will become obvious tothose skilled in the art by reference to the accompanying drawingswherein:

Figure 1 is an end view of the X-ray examination table of the presentinvention in radiographic position,

Figure 2 is a view similar to Figure 1 but showing a position to which apart of the apparatus is moved for fluoroscopic examination,

Figure 3 is a side view of the X-ray examination table of the presentinvention as shown in Figure 1,

Figure 4 is a fragmentary top plan view of the table as shown in Figure2,

Figure 5 is a detail view on an enlarged scale of a part of theapparatus for moving fluorescent screen in accordance with the presentinvention,

Figure 6 is a fragmentary perspective view of the fluorescent screen andthe collapsible sup porting arrangement for moving the screen out of theX-ray field during a radiographic examination as shown in Figure 2,

Figure 7 is a schematic view somewhat similar w to Figure 2 and showingthe position of the parts and the counter-weight therefore during themaking of a fluoroscopic examination.

Figure 8 is a schematic view identical to Figure 7 but showing movementof the counterweight in response to movement of the fluorescent sc'reento a new position relative to the table top,

Figure 9 is a schematic view similar to Figure 7 but showing theposition of the various parts during the making of a radiographicexamination.

Figure 10 is a View identical to Figure :9 but showing movement of thecounter-weight in .response to movement of the X-ray tube and supportrelative to the table top during the making of a radiographicexamination,

Figure 11 is a view similar to Figure '7 .and showing the fluorescentscreen in its lowermost position relative to the table top, and

' Figure 12 is a schematic view showing movement "of the counter-weightin response to collapsing of the fluorescent screen toits'fixedpositi'on out of the iX-lray field preparatory "to the makingof a radiographic examination.

Referring now to the drawings in 'detail the -X-ray examination table ofthe present invention tiltingthe tabletop, 'such'ifor exampleas anelectric motor (not shown). This motor is operated :by aifoot switch-6and rotates a shaft which car- :riesa gear I at each end meshing witharcuat'e rack-bars t welded or otherwise aiflxedto sect'ors 8 andconstituting standards forthe table top ll). lhuswupon operation ofrth'e'motor, the'standards 9 are rotated by the rack bars 3 about animaginary pivot as the sectors 9 slide over the base 5.

It willbe noted from Figure 3 that 'the'sectors :or uprights '19 :areprovided with horizontal slots 12 and I3, and spaced tslightly beneaththe table top are a pair of rails or the like 1'4, upon which afluoroscopic carriage [5 provided with rollers '46, iswarranged to movelongitudinally of the table top ID. The carriage 15' is also providedWithadditional rollers l1 '(Figures 1 and 2) engag-ing a horizontallydisposed frame or the #like *8, which forms atelescopic connection withthat portion "of the carriage 15 disposed below the table top I 8. Suchframe H3 in turn supports a verticallypositione'd tower or column 19 'ofchannel shape on its front and rear surfaces to 'form tracks 20 and '22,as shown more clearly in Figure 6.

5A fluorescent screen carriage 23 is movable verticallytupon the tracks20 on the frontfabe of the tower l9 while an X-ray tube carriage "2Elikewise is vertically movable upon the tracks '22 formed on the rearsurface of the'tower l9. Pivotally secured to the X-raytube carriage 24at 25-:isan X-ray tube support assembly which comprises aflpivote'dmember '26 carrying'a counter- Weight 21 at one end and a horizontallyextending arm 28 at its other end. -As shown more clearly in Figure l,thisarm28 carries the X--ray tube'housing :29 at its free .end and inorder to enable rotary motion of the X-ray tube and-housing29 the arm 28is .rotatablysecured to the pivoted member 26. TheX-raytube disposedwithin the-housing '29 is supplied :with'high potential electricalenergy throughinsulated cables 30 extending to 'a high tensiontransformer, in the customary manner.

.:B,y reference now :more particularly to Figure 6, it will be notedthat the fluorescent screen carriage 23 is arranged to support afluorescent screen frame 32, carrying a fluorescent screen'- 33, througha collapsible toggle connection. Sucharrangement comprises a pair oflink members and 35 ,pivoted at 36 and-31 to the carriage 23 and to thefluorescent screen frame 32 at points 38 and 39, with one of these linkmem.- bers 35 having an extension in the form of a] sector .40 as shownin Figure 5. A further pair of slightly curved toggle links 42 and 43are piv-v oted at (it and 5 to the carriage 23 and at their oppositeends are pivotally connected to a pair of links it and i'i,respectively, with the pivot pin (18 being elongated and engageable by acatch "is operable by a lever 59 carried by the screen vframe '32. Theopposite ends of these latter links are in turn pivotally connected to apair of upstanding lugs 52 and .53 secured to the screen frame 32, withthe pivot pin 54 passing through 1 In order to counter-balance both the'fluorescent screen-and frame, as well a-s the *X-ray tube supportingassembly, .a counter-weight 55 is vertically movable interiorly of thetower or cob nmn ieupon suitable rollers 51 (Figure 3-). can be seenfrom Figure 3, as well as "from th'e schematic showing of Figures 7 to12, a pair or.

anda s'nn'lar pairof pulleys '63 and-64 are-disposed adjacent the bottom0f the column 13. A chain or cable 65 extends from the counter-Weight 56around the "pulley -64, thence around =p1-illey 59, to; pulley 15.3:andaround the latter to the upperedge of the SECt0I '4Qit0 which oneend-of the canes-5i is connected, as shown-in Figure 5. Another end ofthis cable '65 is connected to the lower edge of the sector 49 andpasses upvvarcll-vover' the pulleytfi, around the latter 'to pulley =8,thence aroundithe .upper pulley 62, and downwardly "to thecounter-weight 56.

,Byreferenc'e toIFigur-es"? and 8,'=Which1-shoW" the apparatus inposition for the making-of 'afiuoroscopic examination with the X-ray'tube'i29 dis posedibelow the tabletop, it will-'beseen that thefluorescent screen carriage 2-3 is 'connected'directly to :thecounter-weight '56. Consequently, :as the carria'ge' zs is movedvertically of the column I! for atotal travel of approximatelyfifteeninches, the-countei weighttt" also moves a like distance in an oppositedirection within the column ,llinasshown by the arrows inFigure 8.

Assuming 'IIOW the troentgenolqgi's't ,fiesires make a radiographicexposure, the 'X-ray tube support -26 is rotated about .the,,pivotl25Tto move the X-ray tube '29 from below the table .top, shown'in Figures2, 7, .andt8, 113.0 a positionpahdve the table top as shown in Figures1, 3,39 andt-IO. lfn'order -to adjust the tube-to-obj ect distance, theroentgendlogist moves the tube relative to ilthe table-top whichcausesvertical movementpf .the X raytube carriage 24- riding .on the column19.. As the tube-to-object distance is increased. as. shown by the upperarrow in "Figure I0, fthe' counter-weight 5'5 moves vertically within.Ithe column Win an opposite direction'but twice the distance "ofvertica'lmovem'ent o'f the 'xerayitiihe 29 relative to the tabletop, as.shown byitheLlow'er arrow in Figure 10.

It can thus be seen that the counter-weight" 56 follows directlymovement of the fluorescent screen carriage t3 and must be sumcient tocounter-balance the latter because, during movement of the screencarriage 25, the X-ray tube carriage mi remains fixed which thus fixesthe position of the pulleys t8 and as carried by the X-ray tube carnage24. On the other hand, during movement or the X-ray tube carriage Hi thefluorescent screen carriage 23 remains fixed, as hereinafter pointedout, so that the pulleys 5t and 59 change their position which resultsin the counter-weight to moving twice the distance of movement of theY-ray tube 25 relative to the table top. Moreover, due to sucharrangement the X-ray tube carriage and associated parts may be twice asheavy as the fluorescent screen carriage, yet both are perfectlycounter-balanced by the same counter-weight 5b.

Naturally, in order to make a radiographic examination, it is necessarythat the fluorescent screen be out of the field of the X-rays from theX-ray tube 25 when positioned above the table top. Preparatory torotating the X-ray tube 25 from below the table top, as shown in Figures2 and 11, to its position above the table top as shown in Figures 1, 9and and the roentgehologist first operates the lever to which thusdisengages the catch 49 from elongated pivot pin 48. Upon suchdisengagement the fluorescent screen frame 32 carrying the fluorescentscreen automatically moves to an angular position of about 30 withrespect to the tower or column iii, as shown in Figures 2 and 12. Suchautomatic movement is due also to the counter-balancing by the unitarycounter-weight 56 which moves downwardly, a distance such as shown bythe shortest arrow in Figure 12. Since the ends of the cable 65 are, ashereinbefore mentioned, connected to opposite edges of the sector as,this takes up the slack in the cable 55 as the sector moves about itspivot 37, enabling the counter-weight 55 to balance the screen frame 32in its 30 angular position, even though the fluorescent screen carriage23 remains stationary on the column l9 due to the lock 66. 7

Automatic movement of the fluorescent screen frame 32, in response tothe counter-balancing as above described to a position of 30 relative tothe column it, occurs by virtue of the rotation of the link members 34and 35 (the latter including the sector 55) about their respectivepivots 36 and 31. This causes a downward thrust on the pivots s8 and 39which in turn causes rotation of the screen frame 32 about the pivotscomprising the lugs 52 and 53. Such movement of the screen frame 32causes the link arrangement to collapse with the toggle links 42 and "t3moving toward each other about their respective pivots t4 and 35 andcarrying with them the links 4'6 and All which are pivoted thereto andto the lugs 52 and 53. Once the frame 32 has automatically moved to its30 angular position, the operator need then only apply a slight pressureto the frame pushing it into a position parallel to the column l9, whereit is then held in such position by the elongated pivot pin 5 passingbeneath the catch 55, as shown in Figure 1. In moving the screen framefrom its angular position to that parallel with the column it, thesector 45 again makes the cable 55 taut and the counter-weight 55 movesdownwardly a distance represented by the difference between that shownby the shortest and longest arrows in Figure 12.

When it is desired to again return the fluorescent screen frame inposition for a fluoroscopic examination parallel to the table top, theoperator need only release the latch 55 by raising a handle 57 whichcauses the latch 55 to slide away from above the pivot pin 55. Thescreen frame is then pulled away from the column iii until it againreaches its approximately 30 balanced position at which time the sectorat will have again taken up the cable slack and raising thecounter-weight 56 to a position where it again counter-balances thescreen frame 32. From this 30 angular position to the horizontal abovethe table top, then requires very little force due to completecounter-balancing. Upon release of the lock 66 the carriage 23 is thenfree to move vertically of the column l9 under full counterbalancing ofthe counter weight 55 as before explained.

It can thus be seen from the foregoing that an X-ray examination tableis herein provided, in which a single radiographic-fluoroscopic assemblyis carried by the table with but one X-ray tube being employed, and suchX-ray tube is readily movable from a fluoroscopic position below thetable top to a radiographic position above the table top, and viceversa. Moreover, a unitary counter-weight is employed forcounterbalancing vertical movement of the radiographic elements of theassembly and vertical movement of the ,fiuoroscopic elements thereof, aswell as counter-balancing movement of the fluorescent screen frame in anangular position between the horizontal and vertical. Also thefluorescent screen frame carrying the fluorescent screen is supported bytoggle link arrangement from the fluorescent screen carriage whichfacilitates the ease and rapidity with which the screen can be movedinto a fixed position perpendicular to the table top and thus out of thefield of X-radiations during a radiographic examination.

Although one embodiment of the present invention has been shown anddescribed, it is to be understood that further modifications thereof maybe made without departing from the spirit and scope of the appendedclaims.

I claim:

1. An X-ray examination table comprising "a base, a table top rotatablewith respect to said base from a position below the horizontal to avertical position, a carriage movable longitudinally of said table top,a column carried by said carriage and laterally adjustable with respectto said. table top, a radiographic assembly provided with an X-ray tubeand movable longitudinally along said column to adjust said X-ray tuberelative to said table top and including a pivoted member carrying saidX-ray tube at one end for swinging said X-ray tube below said table topfor a fluoroscopic examination and to a position above said table topfor a radiographic examination, a fluoroscopic assembly movablelongitudinally along said column independently of said radiographicassembly including a fluorescent screen and frame movable by theoperator to a position parallel to said table top during a fluoroscopicexamination and to a position perpendicular to said table top during aradiographic examination, and a unitary counter-weight movablelongitudinally along said column and connected to said radiographicassembly and said fluoroscopic assembly for counter-balancing both ofsaid assemblies in all longitudinal positions thereof as well ascounter-balancing fiuorescent screen and frame in an angular positionwith respect to said table top. 5

. s'creen l 41 frame n graphic assembly and said fluoroscopic ass amass?nally of said table .top,.a column carried bysaid 5 carriageandlater'ally adjustable with respect 50.0

said table top, v a .radioe ragchic assembly provided with :an X-raytube and movable longitudinally along said columnsto. adjust saidX-rayltube [relative to said table tnp and including ,a pivoted @110member carrying said tube vat oneaend. for swinging said tube-below saidtable top for a fluoroscopic examination .and .to a position .above saidtable topic-fa radiographic examination, a fluoroscopic assembly.movable longitu- 5 dinally. along said .columnrindependently of saidradiographic -.ass'embly including a fluorescent screen and framemovable by the operatorto .a

"position parallel toisaidi tabletop duringv a fillersoscopicexaminationand to a .lposition perpen- ,go

dicular to c. said table ltgp fillrillg aradie rei hi examination, and,a unitary ..coun er-..weiah en mooted to said ceramic assembly andmavable longitndinallyalonc said ceillmn a d stanc equal to twice .thefdistance of travel ,of said radio- 5 graphic ass mbly tocounteielqalanee he l te i -a-l1its lon itudinal .nositions along saidenlllmn, said, unitary flOllntfilf-flflfiightbein al o connect to saidfluoroscopic assembly ,an imovabie n itudinally along said-column,afiistailceedualto the distance of trayelioi said tli lresoop a smblyio. countehhalaneei latte: nial i s .Yertical spe itiens alonsaiccelum and aid uni ary -.counter -w.eieht bein ice illeq ied to s ifluore nba i n ih same a al au a 'eos l w res eet. to eai ta topa u tablemra ti tine a -,be. e a t ble s e lei. ab e will; i eeee s to, Sai

fa'ffiuo'r'oscoyjic examination and to a positionjo abov'esaidtableltbzi for a- 'fadiographic examinatio'n,' a 'flnoroscopic assemlcily'hiovable longitu- .ani'any along said" column independently ofsaidradiograp hic I? if? 'fir' cludi'ng' fluorescent a to ,saijdltaliie topduringj "flun'atio'x'i anc'l provided with a toggle nt 7 collapsible init l ie direction of position f oios'c'op'ic exa link arrange saidcommito be moved to "afgosition perpendicular to said li b e p dllr ae arede ma x mi n a unitary counterrw eight movable lonaitudinally l e S 19and ee n ili ai l aefoi nt rrbe ane ll lenti -p ei esteem. r a e t d lpeilio l ilie ee s We a l e mo m n 3. 51 'iluo eee Sc een nd frame to aconnter balanced ang ular position with respeot to sai d -tabl e topupon collapse of i'lo said toggle arrangement by an operator.

An Xr a ea m na e tab mpri i a base, a le to rot tabl w th res t sa baso a ne liion e ew e h riz n a ,said tabletop, a radieerenhieas enibly.p.

the horizontal to a -40 jle by the'operator to 2.1.55

7.. s s i vem i ee etlen by ator to enable said fluorescent 'scre'en'andframe ,00

nally of said-table topha .eelumn earrieidzb i-said carriage andslaileallyladjlldi apl h see t m sled with an ray .tube and movable onlldinally along, said columntoadjuet aid Xfliay 1 3 5129 Q I've to saidtable top includi a lpiyeied member carry ng said X-r yillloe at eneendi32 swinging S3 Q.X-. .iy; lb b l saidta le teniq a fluoroscopicexamination and 15.0 a pee en .aboiresaid table-stop fcra radesraphicexa .tion, a fluoroscopic carriage movable lon itudi- .nallyalong .said col mn independently of ai .radiographic assembly, flu recent screen an frame connect d tesai l flu *oscopie carria eb a iscgglearrangement includin a phirality ef piyoted linl-zs collapsible a p anepar llel said tabletop at 1 1 5351 11 .o an ppera er to. enabl saidfluorescent vscreen. and frame .11 automatically m v to an an ularposition and thenc meved joy thecpezater tea ees ti nrgerp nd 'cul .i-ovsaid tabletop .durinecairadie r nhicex inaa unitary canister-we ghtmovable leneitndina ly aion csaid column a d mated to .said .radioc ap eas embly .andsaidifl lloro cqpl base, .a table topvizotatable withrespect to .sai base from apositionbslowsthe horizontalto, a. verticaeesition, a carriage .mcmbleleneitndina l ofsaidta le ep, avcolumncarriedlgy said carriage .and laterally adjustable with. respect to saidtable tone sradiogizaphic assemblylmevable lon i udisnallyvon saidcolumnand ineiudinga pivo ed member carryin anxeray-tuhe atsoneend for swin.ingfisaid Xr. lE '..I1lbfi.h19l said table v tqpiora fluoroscopicexamination and ea nosi ien abov said table top. for ,a radiosraphicexamination, fluoroscopic carriage ,mevame slengitudinally .Qf saidcolumn, a,filiorescentscreenland frame.-.piv -tgtallyuconnected .by.avrpair of brackets tosai fluoroscopic carria e, a collapsible to learrangement connected to said fluoroscopic carriagecarid naidfiuorescent screen frame comprisinga p of to l slinksizerticallyipivnted-to said carria e andmto a pair of linkmelnbers inturn vertically nei sa fiu s e w er en .i ramein an an ula e esltiq w thr spect i e..-se p1 tab e ten- 6. A rad o raphi .fluerQs Q -i a p a u con s n e eelumn a .raei e'raphle ass mpl provided wi h a a tiiibe and movb v ri y loncsaid eelumn to. a us s i X- ay i be r lative tosaid ta leioi l l pivo ed emhe s n qri c sa Xrre tu -le n M swie neealdr Xawfiflleeto ex t on be ow he. elveieeiniqfeeid; ,i lemb r fe' l verticalposition, ae rr a v bl eliud "w i-l on examieaiinane abeye 5 59b P 9point for a radiographic "examination, a fluoroscopic assembly movablevertically along said column independentl of said'radiographic assemblyincluding a fluorescent screen and frame movable by an operator to ahorizontal position during a fluoroscopic examination and to a positionparallel to said column during a radiographic examination, and a unitarycounter-weight movable vertically along said column and connected tosaid radiographio assembly and said fluoroscopic assembly forcounter-balancing both of said assemblies in all vertical positionsthereof as well as counter-balancing said fluorescent screen and framein an angular position between the horizontal and vertical.

'1. A radiographic andl'fluoroscopic apparatus comprising a column,a'radiographic assembly provided with an X-ray tube and movablevertically along said column: to adjust said X-ray tube relative to saidtable top and including a pivoted member supporting said X-ray tube atone end for swinging said X-ray tube to a position below the pivot pointof said member for a fluoroscopic examination and above such pivot pointfor a radiographic examination, a fluoroscopic assembly movablevertically along said column independently of said radiographic assemblyincluding a fluorescent screen and frame supported by a collapsibletoggle connection including a plurality of pivoted links to saidfluoroscopic assembly to enable said fluorescent screen and frame to bemoved at the will of an operator to ahorizontal position for afluoroscopic examination and to a vertical position parallel with saidcolumn during a radiographic examination, and a unitary counter-weightmovablevertically along said column and connected to said radiographicassembly and said fluoroscopic assembly for counterbalancing both saidassemblies in all vertical positions thereof as well ascounter-balancing said fluorescent screen and frame in an angularposition between the horizontal and vertical.

8. A radiographic and fluoroscopic apparatus comprisin a column, aradiographic assembly provided with an X-ray tube and movable verscopicexamination and above such pivot point for -fa radiographic examination,a fluoroscopic asseihbly movable vertically along said columnindependently of said radiographic assembly includmg" a fluorescentscreen and frame supported by a.;collapsible toggle connection includinga plur'ality of pivoted links to said fluoroscopic assembly to enablesaid fluorescent screen and frame to bej moved at the will of anoperator to a horizontal position for a fluoroscopic examination and toa position parallel with said column during a 'radiographic examination.

.9. A radiographic and fluoroscopic apparatus comprising a column, aradiographic assembly movable vertically on said column including apivoted member supporting an X-ray tube at one end for swinging saidX-ray tube to a position below the pivot point of said member for afluoroscopic examination and above such pivot point for a radiographicexamination, a fluoroscopic assembly movable vertically on said columnincluding a carriage, a fluorescent screen and frame pivotally connectedby a pair of brackets to said carriage, a collapsible toggle arrangementconnected to said fluorescent screen and frame and to said fluoroscopiccarriage comprising a pair of toggle links vertically pivoted to saidcarriage and to a pair of link members in turn vertically pivoted tosaid fluorescent screen frame, with said pairs of links ."beingcollapsible in a horizontal plane about their respective vertical pivotsto cause rotary movejment of said pair of brackets about their pivots,

tically along said column to adjust said X-ray tube relative to saidtable top and including a pivoted member supporting said X-ray tube atone end for swinging said X-ray tube to a position below the pivot pointof said member for a. fluoroaccompanied by movement of said fluorescentscreen and frame from a horizontal position for a "fluoroscopicexamination to a vertical position parallel with said column during aradiographic examination.

OSWALD CONRAD HOLLSTEIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,623,043 Gro'be May 10, 19272,060,981 Fischer et a1 Nov. 17, 1936 2,311,581 Simmon Feb. 16, 19432,315,786 Grobe Apr. 6, 1943

